51% of the Doctor's adventures have been set in the future

51% of Doctor Who's stories have been set in the future while 23% have been set in the past. Earth has been the most popular location (47% of stories set on the planet) while another 33% of stories have been set in alien worlds, 16% on spacecraft or space stations and 4% on 'other realms' according to to the BBC's Doctor Who bible, Who-ology.

71 hours and 37 minutes - the amount of time spent on screen by Tom Baker as Doctor Who

Tom Baker as Doctor Who. Photograph: BBC

Tom Baker holds the record as the Doctor who has spent most time on screen - 71 hours and 37 minutes in all of his regular episodes, while Paul McGann's one episode revival game him only one hour and four minutes screen time overall until that was bumped up by the recent three minute short 'Night of the Doctor'.

28 - the highest number of story appearances by any one Doctor Who companion

Karen Gillan as Amy Pond in Doctor Who. Photograph: BBC/BBC

Amy Pond, played by Karen Gillan, appeared as Doctor Who's companion in 28 stories - the most of any of the Doctor's companions. Pond and Rose Tyler have both featured in 33 episodes of the show but according to Who-ology, Tyler is in second place having featured in 26 stories.

27 years old - the youngest actor to play Doctor Who

Matt Smith is the youngest ever actor to have taken on the role of Doctor Who. Photograph: BBC/PA

Matt Smith who was 27 by the first time his first episode aired, is the youngest ever actor to have played the Doctor. Prior to Smith, Peter Davison who became the fifth Doctor Who, was the youngest actor to take on the role.

Eight different Sonic Screwdrivers

The first appearance was in Fury from the Deep. It stopped featuring in the classic series of Doctor Who after the Terileptils destroyed the fifth Doctor's Sonic Screwdriver. The shortest-lived version of it was Paul McGann's, which only lasted for the length of Doctor Who - The Movie. It can open doors, scan computers and even as a normal screwdriver but it just won't work on wood. Everything has its limitations.

62% of Doctor Who's companions have been female

Billie Piper as Rose Tyler, one of the many female companions of Doctor Who. Photograph: BBC

Doctor Who has had a variety of companions over the years and according to Who-ology the majority of his companions have been female. 33% have been male and 5% are classed as robots. And the most popular reason for joining the Doctor? Why, being invited of course - although being 'forced on the Doctor' and 'accidentally taken' are joint second according to the BBC book.

Six - versions of the Tardis

Doctor Who's Tardis. Photograph: BBC

During the 50 year history of the show, the iconic time machine and spacecraft from Doctor Who has undergone a few transformations - there have been six different designs in fact. The latest version was introduced along with the eleventh doctor.

22 Daleks - the monster with the most appearances

Doctor Who's 50th anniversary special, which will be broadcast on 23 November is set to feature the Daleks. Photograph: BBC/PA

The Daleks have made it into 22 stories while the second most prolific of the monster grouping, Cybermen have featured in 15 of the Doctor's adventures.

12 years old - considered by the Sontaran warrior race to be a good age to reach

The most famous of the Sontarans to recent fans of the series is the Strax. Originally a nurse he was resurrected and recruited as a butler by Silurian Madame Vastra who lives in the 19th century. Along with Vastra's human lover Jenny, the three make up the Paternoster Gang.

6ft 3in - the height of the tallest Doctors

Jon Pertwee as Doctor Who

At 6ft 3ins, both Jon Pertwee and Tom Baker have been the tallest actors to play the Doctor. David Tennant is the next tallest at 6ft 1ins and Sylvester McCoy at 5ft 6ins is the shortest actor to have played Doctor Who.